Remember the kid that built that wooden bike awhile ago? That thing was sweet and made from trees. And so is this one. Phil Bridge is a 21-year old Industrial Design student that developed a cardboard bicycle. The idea is to make bikes so cheap that nobody will be put off by the thought of buying a bike as a means of personal transportation.

A typical round town bike can cost several hundred pounds. That's a large investment for people who aren't sure whether they will use it. The idea of cardboard is to completely devalue the bike.

Phil's current prototype can hold up to 168-pounds (I'm out), costs $6 to manufacture (frame only, it uses a standard chain mechanism and wheels) and will cost about $24. Allegedly it's even rainproof. It is not, however, fireproof. So be sure to park it inside if you live near a volcano.